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Abstract: Multidisciplinary investigations of the sequence at Beeches Pit, West Stow (Suffolk, UK), have a direct bearing the age of the Hoxnian Interglacial and its correlation with the continental Holsteinian and with the global marine record. At this site, glacial deposits (till and outwash gravels) referable to the Anglian Lowestoft Formation fill a subglacial channel cut in Chalk bedrock. Above these glacial deposits a series of interglacial sediments occurs, consisting of limnic, tufaceous and colluvial silts, lacking pollen but rich in shells, ostracods and vertebrates. Lower Palaeolithic flint artefacts of Acheulian character have also been recovered, including refitting examples. Charred material is abundant at certain horizons and many of the bones have been burned. Several discrete areas of burnt sediment are interpreted as hearths. The molluscan fauna comprises some 78 taxa and includes species of considerable zoogeographical and biostratigraphical importance. The land snail assemblage from the tufa consists of woodland taxa with no modern analogue, including species that are either extinct (e.g. Zonitoides sepultus) or which no longer live in Britain (e.g. Platyla polita, P. similis, Neniatlanta pauli). This is also the type locality of Retinella (Lyrodiscus) skertchlyi, which belongs to a subgenus of zonitid land snail now living only on the Canary Islands. There are indications from this fauna (‘the Lyrodiscus biome’) that the climate was wetter and perhaps warmer than the present day. The vertebrate fauna is also noteworthy with species of open habitats, such as rabbit (Oryctolagus cf. cuniculus), and of closed forest, such as squirrel (Sciurus sp.) and garden dormouse (Eliomys quercinus) present at different times. The occurrence of southern thermophiles, such as Aesculapian snake (Zamenis longissimus), indicates temperatures warmer than those of eastern England today. The upper levels include much material reworked from the interglacial sediments, although there is clear faunal evidence for climatic deterioration. Both the molluscan and vertebrate faunas suggest correlation of the interglacial sediments with the Hoxnian. Uranium series dates from the tufa (∼455ka BP), TL dates from burnt flints (414±30ka BP) and a range of amino acid racemization data all support correlation of this interglacial with MIS 11. However, four OSL dates from sand beneath the interglacial sequence yield a mean age of 261±31kaBP, far younger than all other age determinations and far younger than implied by the biostratigraphy. Archaeologically the site is unusual in showing prolonged human occupation within closed deciduous forest and evidence for controlled use of fire in a Lower Palaeolithic context. Biostratigraphical correlations with other Lower Palaeolithic sites support the suggestion that Acheulian and Clactonian industries both occurred in southern Britain during the same substage of the Hoxnian, although not necessarily at precisely the same time. The characteristics of the MIS 11 interglacial in Britain are discussed in the light of evidence from Beeches Pit and elsewhere. [Copyright &y& Elsevier]

Abstract: The Mid-Brunhes Event (MBE) is a climatic transition occurring between MIS 13 and 11 that separates two climatic modes: (1) early Middle Pleistocene interglacials (780–450ka) that are characterised by only moderate warmth and (2) Middle and Late Pleistocene interglacials (occurring after 450ka) that are characterised by greater warmth consistent with, or warmer than, the Holocene. This event is observable within a variety of long climate records, such as SPECMAP and EPICA, but its effect on terrestrial systems is poorly understood. The impact of this event is examined in the British terrestrial sequence by comparing the occurrence of a range of thermophilous plant and animal species, and climate reconstructions derived from assemblages containing them, from interglacials of the early Middle Pleistocene with those from the late Middle and Late Pleistocene. This comparison reveals that interglacial climates during the early Middle Pleistocene in Britain were as warm as, and in some cases warmer than, those that occurred during the late Middle and Late Pleistocene. This interpretation is supported by sea surface temperature records in the North Atlantic, which show that temperatures during early Middle Pleistocene interglacials were at least as warm as those experienced during the Holocene. There is, therefore, no evidence in climate records of Britain and the North Atlantic for a Mid-Brunhes Event. This suggests that the MBE is not a global climatic transition but is restricted to specific regions, in particular the higher latitudes of the southern Hemisphere. Further work is needed to understand the regional variability and cause of the MBE. [ABSTRACT FROM AUTHOR]